BOISE, Idaho (AP) – Authorities say a Nevada couple’s tip was key to solving the case of two missing Idaho girls so rescuers could get them safely home.

Few knew that the young school-aged sisters from Boise, Idaho, were missing along with their dad when Lester and Kathy Porter decided to take a hike in the hills near the Porter’s home last Thursday.

But the Porters encountered a strange scene while on the walk outside of Eureka, Nevada: A pickup truck on fire, a strangely calm man hiding in the brush, the sound of a crying child. They headed back to notify the fire department and returned to life as usual – until Sunday, when a friend sent them a missing persons flier for a case out of Boise. The flier said 29-year-old Joshua Dundon was missing along with his two daughters.

“Looking at Joshua (on the missing persons flier), we thought this could be the guy in the pickup,” Kathy Porter told ( http://bit.ly/2rgLqdk ) The Idaho Statesman. The Porters alerted the Eureka County Sheriff’s Office – and helped save two children left in the cold, high-altitude desert.

Police say Joshua Dundon was locked in a custody dispute with the girls’ mother when he checked his kids out of elementary school on Wednesday. It was the next day when Dundon’s silver pickup passed the Porters as they walked up a hill toward Richmond Spring.

At the top of the hill, they heard the pickup start to rev its engine.

“We stepped into a little clearing and the pickup suddenly went in reverse in front of us at a pretty high rate of speed. . No one was in the vehicle and the cab of the pickup was on fire,” Kathy Porter said.

The flaming truck hit some rocks and then stopped. Lester Porter shouted a question: Are you OK?

“A man stuck his head out of some brush and said, ‘Yea, I’m OK,'” Kathy Porter said. “He was just way too calm, the way he said it. We immediately knew something was wrong,” Kathy said.

The Porters decided to call for help, but heard a child start to softly cry as they turned away. They couldn’t see the child, but saw the man turn and calmly soothe the child.

They ran to notify authorities and saw a fire truck headed up the hill to extinguish the pickup. By the time the fire was out, the man was gone along with any child or children who might have been with him.

Sheriff’s investigators in Eureka County tried to determine who owned the truck but the vehicle identification numbers and license plates were melted. A gun found at the scene was a dead end, traced to someone who had recently died in California.

Boise police began publicizing the case of the missing girls on Saturday, hoping for the public’s help, and then came the Porters’ tip. The couple was instrumental in understanding the mystery, Eureka County Sheriff Keith Logan said.

On Monday, Joshua Dundon walked up to a Nevada ranch, cold, barefoot and hungry. The ranchers, Vera and Jim Baumann, recognized Dundon from news reports and kept him there while they called authorities.

Dundon told the sheriff and the Baumanns he didn’t have any family, friends or other connections in west-central Nevada. It remains unclear why he and the girls ended up there.

His absence in Boise meant he missed a family intake screening scheduled for Friday in an ongoing custody dispute. The girls’ mother filed the case in January, and Dundon later filed a counterclaim. As the case proceeded, they had joint custody of the girls, according to Boise police.

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